<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<title>System Configuration Files system_&lt;device&gt;.c and system_&lt;device&gt;.h</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<link href="cmsis.css" rel="stylesheet" type="text/css" />
<link href="navtree.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="resize.js"></script>
<script type="text/javascript" src="navtree.js"></script>
<script type="text/javascript">
  $(document).ready(initResizable);
</script>
<link href="search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="search/search.js"></script>
<script type="text/javascript">
  $(document).ready(function() { searchBox.OnSelectItem(0); });
</script>

</head>
<body>
<div id="top"><!-- do not remove this div! -->

<div id="titlearea">
<table cellspacing="0" cellpadding="0">
 <tbody>
 <tr style="height: 46px;">
  <td id="proglogo"><img alt="CMSIS Logo" src="CMSIS_Logo_Final.png"></td>
  
  <td style="padding-left: 0.5em;">
   <div id="projectname">CMSIS-CORE
   &#160;<span id="projectnumber">Version 3.01</span>
   </div>
   <div id="projectbrief">CMSIS-CORE support for Cortex-M processor-based devices</div>
  </td>
  
  
  
 </tr>
 </tbody>
</table>
</div>

<div id="CMSISnav" class="tabs1">
    <ul class="tablist">
      <li><a href="../../General/html/index.html"><span>CMSIS</span></a></li>
      <li class="current"><a href="../../Core/html/index.html"><span>CORE</span></a></li>
      <li><a href="../../DSP/html/index.html"><span>DSP</span></a></li>
      <li><a href="../../RTOS/html/index.html"><span>RTOS API</span></a></li>
      <li><a href="../../SVD/html/index.html"><span>SVD</span></a></li>
    </ul>
</div>
<!-- Generated by Doxygen 1.7.5.1 -->
<script type="text/javascript">
var searchBox = new SearchBox("searchBox", "search",false,'Search');
</script>
  <div id="navrow1" class="tabs">
    <ul class="tablist">
      <li><a href="index.html"><span>Main&#160;Page</span></a></li>
      <li class="current"><a href="pages.html"><span>Usage&#160;and&#160;Description</span></a></li>
      <li><a href="modules.html"><span>Reference</span></a></li>
      <li>
        <div id="MSearchBox" class="MSearchBoxInactive">
        <span class="left">
          <img id="MSearchSelect" src="search/mag_sel.png"
               onmouseover="return searchBox.OnSearchSelectShow()"
               onmouseout="return searchBox.OnSearchSelectHide()"
               alt=""/>
          <input type="text" id="MSearchField" value="Search" accesskey="S"
               onfocus="searchBox.OnSearchFieldFocus(true)" 
               onblur="searchBox.OnSearchFieldFocus(false)" 
               onkeyup="searchBox.OnSearchFieldChange(event)"/>
          </span><span class="right">
            <a id="MSearchClose" href="javascript:searchBox.CloseResultsWindow()"><img id="MSearchCloseImg" border="0" src="search/close.png" alt=""/></a>
          </span>
        </div>
      </li>
    </ul>
  </div>
</div>
<div id="side-nav" class="ui-resizable side-nav-resizable">
  <div id="nav-tree">
    <div id="nav-tree-contents">
    </div>
  </div>
  <div id="splitbar" style="-moz-user-select:none;" 
       class="ui-resizable-handle">
  </div>
</div>
<script type="text/javascript">
  initNavTree('system_c_pg.html','');
</script>
<div id="doc-content">
<div class="header">
  <div class="headertitle">
<div class="title">System Configuration Files system_&lt;device&gt;.c and system_&lt;device&gt;.h </div>  </div>
</div>
<div class="contents">
<div class="textblock"><p>The <a class="el" href="system_c_pg.html">System Configuration Files system_&lt;device&gt;.c and system_&lt;device&gt;.h</a> provides as a minimum the functions described under <a class="el" href="group__system__init__gr.html">System and Clock Configuration</a>. These functions are device specific and need adaptations. In addition, the file might have configuration settings for the device such as XTAL frequency or PLL prescaler settings.</p>
<p>For devices with external memory BUS the system_&lt;device&gt;.c also configures the BUS system.</p>
<p>The silicon vendor might expose other functions (i.e. for power configuration) in the system_&lt;device&gt;.c file. In case of additional features the function prototypes need to be added to the system_&lt;device&gt;.h header file.</p>
<h2><a class="anchor" id="system_Device_sec"></a>
system_Device.c Template File</h2>
<p>The <a class="el" href="system_c_pg.html#system_Device_sec">system_Device.c Template File</a> for the Cortex-M3 is shown below.</p>
<div class="fragment"><pre class="fragment">/**************************************************************************//**
 * @file     system_&lt;Device&gt;.c
 * @brief    CMSIS Cortex-M# Device Peripheral Access Layer Source File for
 *           Device &lt;Device&gt;
 * @version  V3.01
 * @date     06. March 2012
 *
 * @note
 * Copyright (C) 2010-2012 ARM Limited. All rights reserved.
 *
 * @par
 * ARM Limited (ARM) is supplying this software for use with Cortex-M 
 * processor based microcontrollers.  This file can be freely distributed 
 * within development tools that are supporting such ARM based processors. 
 *
 * @par
 * THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
 * OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
 * ARM SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR
 * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
 *
 ******************************************************************************/


#include &lt;stdint.h&gt;
#include "&lt;Device&gt;.h"


/*----------------------------------------------------------------------------
  DEFINES
 *----------------------------------------------------------------------------*/
    
/*----------------------------------------------------------------------------
  Define clocks
 *----------------------------------------------------------------------------*/
/* ToDo: add here your necessary defines for device initialization     
         following is an example for different system frequencies             */
#define __HSI             ( 6000000UL)
#define __XTAL            (12000000UL)    /* Oscillator frequency             */
#define __SYS_OSC_CLK     (    ___HSI)    /* Main oscillator frequency        */

#define __SYSTEM_CLOCK    (4*__XTAL)


/*----------------------------------------------------------------------------
  Clock Variable definitions
 *----------------------------------------------------------------------------*/
/* ToDo: initialize SystemCoreClock with the system core clock frequency value
         achieved after system intitialization.
         This means system core clock frequency after call to SystemInit()    */
uint32_t SystemCoreClock = __SYSTEM_CLOCK;  /*!&lt; System Clock Frequency (Core Clock)*/


/*----------------------------------------------------------------------------
  Clock functions
 *----------------------------------------------------------------------------*/
void SystemCoreClockUpdate (void)            /* Get Core Clock Frequency      */
{
/* ToDo: add code to calculate the system frequency based upon the current
         register settings.
         This function can be used to retrieve the system core clock frequeny
         after user changed register sittings.                                */
  SystemCoreClock = __SYSTEM_CLOCK;
}

/**
 * Initialize the system
 *
 * @param  none
 * @return none
 *
 * @brief  Setup the microcontroller system.
 *         Initialize the System.
 */
void SystemInit (void)
{
/* ToDo: add code to initialize the system
         do not use global variables because this function is called before
         reaching pre-main. RW section maybe overwritten afterwards.          */
  SystemCoreClock = __SYSTEM_CLOCK;
}
</pre></div><h2><a class="anchor" id="system_Device_h_sec"></a>
system_Device.h Template File</h2>
<p>The system_&lt;device&gt;.h header file contains prototypes to access the public functions in the system_&lt;device&gt;.c file. The <a class="el" href="system_c_pg.html#system_Device_h_sec">system_Device.h Template File</a> is shown below.</p>
<div class="fragment"><pre class="fragment">/**************************************************************************//**
 * @file     system_&lt;Device&gt;.h
 * @brief    CMSIS Cortex-M# Device Peripheral Access Layer Header File for
 *           Device &lt;Device&gt;
 * @version  V3.01
 * @date     06. March 2012
 *
 * @note
 * Copyright (C) 2010-2012 ARM Limited. All rights reserved.
 *
 * @par
 * ARM Limited (ARM) is supplying this software for use with Cortex-M 
 * processor based microcontrollers.  This file can be freely distributed 
 * within development tools that are supporting such ARM based processors. 
 *
 * @par
 * THIS SOFTWARE IS PROVIDED "AS IS".  NO WARRANTIES, WHETHER EXPRESS, IMPLIED
 * OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
 * ARM SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL, INCIDENTAL, OR
 * CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
 *
 ******************************************************************************/


#ifndef SYSTEM_&lt;Device&gt;_H   /* ToDo: replace '&lt;Device&gt;' with your device name */
#define SYSTEM_&lt;Device&gt;_H

#ifdef __cplusplus
extern "C" {
#endif

#include &lt;stdint.h&gt;

extern uint32_t SystemCoreClock;     /*!&lt; System Clock Frequency (Core Clock)  */


/**
 * Initialize the system
 *
 * @param  none
 * @return none
 *
 * @brief  Setup the microcontroller system.
 *         Initialize the System and update the SystemCoreClock variable.
 */
extern void SystemInit (void);

/**
 * Update SystemCoreClock variable
 *
 * @param  none
 * @return none
 *
 * @brief  Updates the SystemCoreClock with current core Clock 
 *         retrieved from cpu registers.
 */
extern void SystemCoreClockUpdate (void);

#ifdef __cplusplus
}
#endif

#endif /* SYSTEM_&lt;Device&gt;_H */
</pre></div> </div></div>
</div>
  <div id="nav-path" class="navpath">
    <ul>
      <li class="navelem"><a class="el" href="_templates_pg.html">Template Files</a>      </li>
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
     onmouseover="return searchBox.OnSearchSelectShow()"
     onmouseout="return searchBox.OnSearchSelectHide()"
     onkeydown="return searchBox.OnSearchSelectKey(event)">
<a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(0)"><span class="SelectionMark">&#160;</span>All</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(1)"><span class="SelectionMark">&#160;</span>Data Structures</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(2)"><span class="SelectionMark">&#160;</span>Files</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(3)"><span class="SelectionMark">&#160;</span>Functions</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(4)"><span class="SelectionMark">&#160;</span>Variables</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(5)"><span class="SelectionMark">&#160;</span>Enumerations</a><a class="SelectItem" href="javascript:void(0)" onclick="searchBox.OnSelectItem(6)"><span class="SelectionMark">&#160;</span>Enumerator</a></div>

<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0" 
        name="MSearchResults" id="MSearchResults">
</iframe>
</div>


    <li class="footer">Generated on Wed Mar 28 2012 15:37:44 for CMSIS-CORE by ARM Ltd. All rights reserved.
    <!--
    <a href="http://www.doxygen.org/index.html">
    <img class="footer" src="doxygen.png" alt="doxygen"/></a> 1.7.5.1 </li>
    -->
    </li>
   </ul>
 </div>


</body>
</html>
